Dehydration of industrial isopropanol wastewater by pervaporation using carboxy methyl cellulose and graphene oxide hybrid membranes

Abstract

Isopropanol (IPA) is widely used as an industrial solvent, cleaning agent, and in producing chemicals, fuels and medical products. Many applications require anhydrous IPA without water. IPA-containing wastewaters are generated from its production and uses. Dewatering and recycling IPA from these waste streams is important for both economic and environmental reasons. IPA and water form an azeotropic mixture, making conventional dehydration methods like distillation and extraction challenging. Membrane-based processes such as pervaporation offer advantages over these processes, as it can break azeotropes while requiring lower energy and having a smaller footprint. In this study, hybrid membrane was used to dehydration of industrial isopropanol wastewater by pervaporation. The study focused on preparing hybrid membranes for pervaporation dehydration by incorporating graphene oxide into a carboxy methyl cellulose matrix. This integration of graphene oxide led to an enhancement in the dehydration separation performance of the hybrid membranes. Additionally, the research systematically characterized and evaluated the impact of graphene oxide concentration, operation temperature, and feed IPA concentration on various properties such as hydrophilicity, swelling, and dehydration. These analyses aimed to understand the influence of these factors on the overall performance and properties of the hybrid membranes. Optimum process conditions have been determined and under these conditions, water flux 4.7 kg/m2h and separation factor value of 128 were obtained. The study's findings pave the way for the future development of carboxy methyl cellulose (CMC) based hybrid membranes for implementation in pervaporative dehydration processes. © 2024 Bulgarian Academy of Sciences, Union of Chemists in Bulgaria.